X11 — Cyber Threats, Attacks & Incidents

Threat entity extracted from intelligence sources

Frequency
5
occurrences
First Seen
November 18, 2025
Last Seen
July 14, 2026

X11 is a technology platform tracked by ThreatCluster, appearing in 6 threat clusters built from 5 intelligence report mentions.

X11 is a technology platform tracked across 6 threat clusters and 5 intelligence report mentions on ThreatCluster. First observed November 18, 2025; most recent activity July 14, 2026.

Related Threat Clusters

  • Critical OpenSSH Vulnerability Allows Privilege Escalation on Ubuntu Systems

    A critical vulnerability in OpenSSH has been identified, affecting Ubuntu systems, particularly version 16.04. The flaw arises from improper handling of file permissions when downloading files as root using the legacy…

    4 articles · Updated July 6, 2026
  • ClipXDaemon Malware Targets Cryptocurrency Users on Linux

    Security researchers have identified ClipXDaemon, a new malware strain targeting cryptocurrency users on Linux systems. This stealthy clipboard hijacker manipulates copied wallet addresses and is delivered through a…

    4 articles · Updated March 9, 2026
  • Critical FVWM3 Vulnerability Across Fedora Versions CVE-2025

    A critical command injection vulnerability has been identified in FVWM3, a window manager for X11, affecting Fedora versions 41, 42, and 43. The vulnerability has been addressed with an update to FVWM3 version 1.1.4,…

    3 articles · Updated November 18, 2025
  • Fedora 42 and 43 Fvwm3 Security Patch for CVE-2025-65637

    Fedora has released crucial patches for the Fvwm3 window manager to address CVE-2025-65637, a denial-of-service vulnerability. Users of Fedora 42 and 43 are affected, and the updates aim to mitigate potential…

    2 articles · Updated February 19, 2026
  • Multiple OpenSSH Versions Released with Security Enhancements

    On July 13, 2026, three new versions of OpenSSH were released, specifically 1:10.2p1-2ubuntu3.4, 1:8.9p1-3ubuntu0.16, and 1:9.6p1-3ubuntu13.18. These updates include various security features and enhancements for the…

    3 articles · Updated July 13, 2026
  • Critical FVWM3 Vulnerability Addressed in Fedora Updates

    Fedora has released critical updates for the FVWM3 window manager to address a command injection vulnerability identified as CVE-2025. The updates affect multiple Fedora versions, including 41 and 42, with the latest…

    3 articles · Updated November 18, 2025

Recent Intelligence Reports

  • 1:10.2p1-2ubuntu3.4 — launchpad.net · July 14, 2026
  • ClipXDaemon Malware, a Stealthy Cryptocurrency Clipboard Hijacker on Linux — Thecyberexpress · March 9, 2026
  • Fedora 42 fvwm3 Crucial Service Disruption Patch 2026 — Linuxsecurity · February 19, 2026
  • Fedora 43 Fvwm3 Important Denial-of-Service Security Patch CVE-2025 — Linuxsecurity · February 19, 2026
  • Fedora 42: fvwm3 Critical CVE-2025 — Linuxsecurity · November 18, 2025

Frequently asked questions

What is X11?

X11 is a technology platform tracked by ThreatCluster, appearing in 6 threat clusters built from 5 intelligence report mentions.

Is X11 still active?

The most recent intelligence report mentioning X11 on ThreatCluster is dated July 14, 2026. Activity was first observed November 18, 2025, giving a tracked span from then to July 14, 2026.

What is X11 associated with?

Across ThreatCluster reporting, X11 most frequently co-occurs with DDoS, Denial-of-Service, Malware, bc1qe8g2rgac5rssdf5jxcyytrs769359ltle3ekle, Fedora, among 12 tracked related entities.

What are the latest developments involving X11?

The most significant recent cluster is “Critical OpenSSH Vulnerability Allows Privilege Escalation on Ubuntu Systems” (4 articles · Updated July 6, 2026). X11 appears across 6 threat clusters in total, listed above with sources.

How much reporting does ThreatCluster have on X11?

X11 appears in 5 intelligence report mentions across 6 deduplicated threat clusters, aggregated from 17,000+ monitored sources.

CVSS v3.1 Breakdown